Length -- 4.75 to 5 inches. About an inch and a half shorter than the English sparrow.
Male -- Black cap; yellow forehead; all other upper parts olive-green; rich yellow underneath.
Female -- Lacks the black cap.
Range -- North America, from Alaska and Nova Scotia to Panama.
Winters south of Gulf States. Nests chiefly north of the United States.
Migrations -- May. September. Spring and autumn migrant.
To see this strikingly marked little bird one must be on the sharp lookout for it during the latter half of May, or at the season of apple bloom, and the early part of September. It passes northward with an almost scornful rapidity.
Audubon mentions having seen it in Maine at the end of October, but this specimen surely must have been an exceptional laggard.
In common with several others of its family, it is exceedingly expert in catching insects on the wing; but it may be known as no true flycatcher from the conspicuous rich yellow of its under parts, and also from its habit of returning from a midair sally to a different perch from the one it left to pursue its dinner. A true flycatcher usually returns to its old perch after each hunt.
To indulge in this aerial chase with success, these warblers select for their home and hunting ground some low woodland growth where a sluggish stream attracts myriads of insects to the boggy neighborhood. Here they build their nest in low bushes or upon the ground. Four or five grayish eggs, sprinkled with cinnamon-colored spots in a circle around the larger end, are laid in the grassy cradle in June. Mr. H. D. Minot found one of these nests on Pike's Peak at an altitude of 11,000 feet, almost at the limit of vegetation. The same authority compares the bird's song to that of the redstart and the yellow warbler.
YELLOW REDPOLL WARBLER (Dendroica palmarum hypochrysea) Wood Warbler family Called also: YELLOW PALM WARBLER; [the two former palm warbler species combined as PALM WARBLER, AOU 1998]
Length -- 5.5 to 5.75 inches. A little smaller than the English sparrow.
Male and Female -- Chestnut crown. Upper parts brownish olive;greenest on lower back. Underneath uniform bright yellow, streaked with chestnut on throat, breast, and sides. Yellow line over and around the eye. Wings unmarked. Tail edged with olive-green; a few white spots near tips of outer quills. More brownish above in autumn, and with a grayish wash over the yellow under parts.
Range -- Eastern parts of North America. Nests from Nova Scotia northward. Winters in the Gulf States.
Migrations -- April. October. Spring and autumn migrant.
While the uniform yellow of this warbler's under parts in any plumage is its distinguishing mark, it also has a flycatcher's trait of constantly flirting its tail, that is at once an outlet for its superabundant vivacity and a fairly reliable aid to identification. The tail is jerked, wagged, and flirted like a baton in the hands of an inexperienced leader of an orchestra. One need not go to the woods to look for the restless little sprite that comes northward when the early April foliage is as yellow and green as its feathers.
It prefers the fields and roadsides, and before there are leaves enough on the undergrowth to conceal it we may come to know it as well as it is possible to know any bird whose home life is passed so far away. Usually it is the first warbler one sees in the spring in New York and New England. With all the alertness of a flycatcher, it will dart into the air after insects that fly near the ground, keeping up a constant chip, chip, fine and shrill, at one end of the small body, and the liveliest sort of tail motions at the other. The pine warbler often bears it company.
With the first suspicion of warm weather, off goes this hardy little fellow that apparently loves the cold almost well enough to stay north all the year like its cousin, the myrtle warbler. It builds a particularly deep nest, of the usual warbler construction, on the ground, but its eggs are rosy rather than the bluish white of others.
In the Southern States the bird becomes particularly neighborly, and is said to enter the streets and gardens of towns with a chippy's familiarity.
Palm Warbler or Redpoll Warbler (Dendroica palmarum) differs from the preceding chiefly in its slightly smaller size, the more grayish-brown tint in its olive upper parts, and the uneven shade of yellow underneath that varies from clear yellow to soiled whitish. It is the Western counterpart of the yellow redpoll, and is most common in the Mississippi Valley. Strangely enough, however, it is this warbler, and not hypochrysea, that goes out of its way to winter in Florida, where it is abundant all winter.
YELLOW WARBLER (Dendroica aestiva) Wood Warbler family Called also: SUMMER YELLOWBIRD; GOLDEN WARBLER; YELLOW POLLLength -- 4.75 to 5.2 inches. Over an inch shorter than the English sparrow.
Male -- Upper parts olive-yellow, brightest on the crown; under parts bright yellow, streaked with reddish brown. Wings and tail dusky olive-brown, edged with yellow.
Female -- Similar; but reddish-brown streakings less distinct.
Range -- North America, except Southwestern States, where the prothonotary warbler reigns in its stead. Nests from Gulf States to Fur Countries. Winters south of the Gulf States. As far as northern parts of South America.
Migrations -- May. September. Common summer resident.